python/cpython#97956: Mention generate_global_objects.py in `AC How…

…-To` (python/cpython#97957)

Doc/howto/clinic.rst

@@ -539,7 +539,15 @@ Let's dive in!
         };
 
 
-16. Compile, then run the relevant portions of the regression-test suite.
+16. Argument Clinic may generate new instances of ``_Py_ID``. For example::
+
+        &_Py_ID(new_unique_py_id)
+
+    If it does, you'll have to run ``Tools/scripts/generate_global_objects.py``
+    to regenerate the list of precompiled identifiers at this point.
+
+
+17. Compile, then run the relevant portions of the regression-test suite.
     This change should not introduce any new compile-time warnings or errors,
     and there should be no externally visible change to Python's behavior.